1. Field of the Invention
The present invention relates to a shield connector to be connected with a shielded cable.
2. Description of the Prior Art
A known shield connector is disclosed in Japanese Unexamined Patent Publication No. 7(HEI)-245153. This connector is described below with reference to FIG. 24.
A shielded cable is identified by W in FIG. 24. A sheath is peeled off at an end of the shielded wire W, thereby exposing a core A1 and a shield layer A2 formed by a braided wire. With the core A1 is connected a male terminal fitting A3. A tubular metal shell A4 is fitted to cover the cable end and the terminal fitting A3, and a rear end thereof (left end in FIG. 24) is forcibly fastened to the shield layer A2. Thereby, the shield layer A2 and the metal shell A4 are electrically connected, forming a shield for the male terminal fitting A3. Although unillustrated, the male terminal fitting A3 and the metal shell A4 are accommodated in a housing.
Since an insulation layer A5 between the core A1 and the shield layer A2 is made of a synthetic resin material, upon being subjected to a high temperature due to heat generated by the core A1, the insulation layer A5 has a reduced rigidity and is liable to be deformed. Accordingly, with the above construction in which the metal shell is forcibly fastened to the shield layer, sealability between the shield layer and the metal shell may be reduced by the reduced rigidity of the insulation layer 5, resulting in an unstable electrical connection.
A further known shield connector of this type is shown in FIGS. 25 and 26.
In FIG. 25, identified by W is a shielded cable. A sheath is peeled off at an end of the shielded wire W, thereby exposing a core B1 and a shield layer B2 formed by a braided wire. A holder B4 provided with a connection fitting B3 is mounted on the end of the shielded cable W and a tubular metal shell B5 (shield tube) is fitted outside the holder B4. This connection fitting B3 is to be electrically connected with the shield layer B2 and the metal shell B5, and opposite ends thereof serve as pressing pieces B3A for holding the shield layer B2 therebetween. Bottom ends of the holding pieces B3A are connected into a mount portion B3B to be mounted on the holder B4.
The holding pieces B3A are open when the holder B4 is mounted on the end of the shielded cable W as indicated by solid line in FIG. 26. When the metal shell B5 is fitted outside the holder B4, upper ends B3C are guided into a fastening slot B5A formed at the opening edge of the metal shell B5. In other words, a distance between the holding pieces B3A is gradually narrowed as the metal shell B5 is mounted. Accordingly, the shield layer B2 is held by the pressing pieces B3A, with the result that the shield layer B2 and the metal shell B5 are electrically connected via the connection fitting B3.
However, with the above construction, the upper ends of the pressing pieces have to be fitted into the fastening slot of the metal shell. Accordingly, an operator has to mount the metal shell while confirming the position of the upper ends of the pressing portions with respect to the fastening slot. This leads to a poor operability. Further, since the pressing pieces are open before the metal shell is fitted, the holder easily rotates with respect to the shielded cable, making it more difficult to fit the upper ends of the pressing portions into the fastening slot.
In view of the above problem, an object of the present invention is to provide an improved shield connector, being particularly capable of securely holding a shield tube and a shield layer electrically connected.